ABSTRACT The objective of the proposed research is to evaluate how patient access and utilization of primary care was disrupted by COVID-19 across three healthcare systems, with a focus on patients with chronic conditions. Our rigorous evaluation has three aims. Aim 1 is to determine whether patients were able to access primary care and, for those who did access care, identification of the modalities to access care (in-person, telehealth (video or phone), asynchronous communication, or multiple modalities). Further, we will identify subpopulations that were disproportionately affected including and may not have been able to access care at all. Aim 2 is to identify barriers and facilitators to digital health access across three sites. Aim 3 is to evaluate how the modality used to access primary care, or the lack of access to primary care, during COVID-19 impacts future healthcare access and utilization for patients with chronic conditions, and other at-risk populations. The research effort is a unique collaborative between MedStar Health, Stanford Health Care, and Intermountain Healthcare. This project utilizes the extensive expertise of the diverse research team which includes data scientists, human factors experts, informaticists, health disparities researchers and clinical experts in digital health. The proposal is directly aligned with AHRQ’s priority area of making health care accessible and safer. To achieve aims one and three we will use rigorous data science and informatics methods. To achieve aim 2, we will use a mixed methods approach that includes interviews of subject matter experts and patients from each of the three sites with a socio-technical systems model as the foundation for our interviews. Contributions from this research will include a detailed understanding of access modalities that are most frequently used, patient populations that may be disproportionately impacted by COVID-19, and identification of barriers and facilitators to digital health models of care. Our rigorous dissemination plan includes communication of results to policymakers and advocacy groups, clinical leaders and other organizations that serve to improve clinical practice, as well as academic audiences. Results from aim 1 will be available within 4- 6 months of project start and the entire project will be completed in two years.